IC-PMX Datasheet, PDF (16/27 Pages) IC-Haus GmbH – ENERGY HARVESTING MULTITURN COUNTER/ENCODER

iC-PMX
ENERGY HARVESTING MULTITURN COUNTER/ENCODER
DEVICE CALIBRATION AND SYSTEM DIAGNOSIS
Rev A3, Page 16/27
BIAS Parameter
The BIAS parameter in each iC-PMX device should be
calibrated to ensure accurate current ramp parameters
and optimal operation of the singleturn sensors. It may
vary from device to device. The best fitting BIAS param-
eter should be stored in the MCU’s nonvolatile memory
for later usage.
Notification of Wiegand Pulses
iC-PMX can send a notification of Wiegand pulses via
the SPI slave interface. This is realized by sending a
16-bit read command which is paused after the 11th
clock cycle. The required opcode is 0x2e. The default
state of the pin MISO is low and it changes to high
during each Wiegand pulse.
Opcode 0x22 is used to set the BIAS parameter. Valid
values are shown in table 10. The current source I(INT)
is driving pin INT of the QFN48 packages and can also
be connected to pin HOP. The nominal value of the
current source is 100 µA. Its value is measured with a
10kΩ resistor against pin VDD.
Send opcode 0x23 with parameter 0x18 to connect
I(INT) with pin HOP. Send opcode 0x23 with parameter
0x00 to quit this test mode.
The active setting of the BIAS parameter can be read
with opcode 0x2a.
BIAS Correction
Value
Description
0x0
-23%
0x1
-20%
0x2
-17%
0x3
-14%
0x4
-12%
0x5
-9%
0x6
-6%
0x7
-3%
0x8
0%
0x9
+6%
0xA
+11%
0xB
+17%
0xC
+23%
0xD
+28%
0xE
+34%
0xF
+40%
Table 10: BIAS Parameter
Device Revision
Opcode 0x2f is used to read the device revision.
Device
Revisions
Value
0x08
0x0A
0x0D
0x0E
Description
iC-PMX 0
iC-PMX 1
iC-PMX 4
iC-PMX 5
Table 11: Device Revision
Figure 4: SPI Communication to Enable Wiegand
Pulse Notification
Figure 5: Wiegand Pulse Notification Through MISO
Pin
End of Current Ramp Detection
The status of the current ramp generator can be read
through the SPI slave interface. This can be used to
detect when the current ramp has finished. See chapter
Wiegand Module Excitation for details.
Pin RDY: Data Ready
Pin RDY is high if V(VDD) and V(VCC) are above the
brownout detection threshold voltage and the power-on
startup routine has finished. This can be used to decide
if the data provided by SPI command Read POS is valid
and if the single turn sensors are ready for operation.